package generic.no1;

import java.util.InputMismatchException;
import java.util.LinkedList;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		int choice;
		Scanner scanner=new Scanner(System.in);
		while (true){
			try{

				System.out.println("""
      
      1.
      2.
						""");
				choice=scanner.nextInt();
				switch (choice){
					case 1:
					case 2:
					default:	System.out.println("选择无效");		continue;
					case 0:		System.out.println("欢迎再次使用！");	return;
				}
			}
			catch (InputMismatchException inputMismatchException){
				System.out.println("选择无效");
			}
		}
	}
}
